Everbody, well almost everybody, knows that beneath Yellowstone National Park (intersecting ID, WY, MT) is an enormous pool of magma close to the surface, the heat from which powers the park's elaborate and often gorgeous collection of thermal features. What I didn't know until a friend in Santa Fe just told me, is that a huge, lush caldera (though smaller than Yellowstone's) can be found 70 miles west of Santa Fe, NM.

That's Yellowstone's Grand Prismatic Pool above, and here's a lovely shot from the Valles Caldera below. More info on the latter, here: https://www.nps.gov/vall/index.htm